Pressing device for cold forming or hot forming workpieces



Feb. 1l, 1964 F. B. HATl-:BUR

PREssING DEVICE FOR com FORMING 0R HOT FORMING woRxPIEcEs 5 Sheets-Sheet1 Filed July 5l, 1961 0 ,b UIMM w. 6 l 9i Il F 5 7 u y l 2 n Y fm 2 /\M\l,

/Nrfwmp Feb. 1l, 1964 F. B. HATE-BUR 3,120,769

PRESSING DEVICE FOR COLD FORMING OR HOT FORMING WORKPIECES Filed July3l, 1961 5 Sheets-Sheet 2 lllll! fg MSSQL,

Feb. l1, 1964 F. B. HA'rr-:BUR 3,120,769

PRESSING DEVICE FOR COLD FORMING OR HOT FORMING WORKPIECES Filed July31. 1961 5 Sheets-Sheet 3 777/1.. Bern fav-ol /a e a-z- Feb. 11, 1964 FB HATEBUR 3,120,769

PREssING DE'VIE: FOR coLD FORMING 0R HOT FORMING woRKPIECEs Filed July31. 1961 5 Shee'cs-SheecI 4 /NVENrUP Feb. l1, 1964 F. B. HATEBU R3,120,769 PREISSING DEVICE FOR COLD FORMING 0R HOT FORMING WORKPIECESFiled July 3l. 1961 5 Sheets-Sheet 5 hws/vm@ United States Patent AO3,120,769 PRESSENG DEJlfCE EUR @ULD FRMEJG QR HOT Fhlt/ENG RKPECES Fritzliernhard Hatebur, Spiegelgasse 4, Easel, Switzerland Filed July 3l,196i, der. i lo. 12S, i9 Claims priority, application Germany Ang. 29,196i) i2. (Claims. (Cl. 7a3-i7) The invention relates to a new orimproved pressing levice for cold forming or hot forming workpieceshaving a varying cross section along their length in the direction ofoperation of a press ram.

ln the case of conventional methods of cold forming or hot formingworkpieces which are provided, for example, with radially projectinganges or radially re-entrant receases, annular grooves or the like orexhibit other inwardly constricted surface portions, forming of theblank into the shape of the workpiece is effected essentially with pressjaws which attack it radially and which close after the blank has beenintroduced into the die cavity. This mode of operation is used forexample in the case of mechanical forges. The known method referred toexhibits the disadvantage that where there are discrepancies in thequantity of material inthe blanks, heavy burrs may occur on the iinishedpieces in the region of the parting lines of the die jaws, because thelatter are closed only after the blank has been introduced into theregion of the -aws. lt is, moreover, difficult to make the pressingeriorts operate radially. On the other hand, it is more favourable ifthe principal forming eilorts operate only axially and their transversecomponents produce the radial forming. A further point is that the typeof press which is more particularly suited for automatic operation isthat in which the blank is inserted axially into the die. The blank isthen subjected to press rams operating axially and is removed-againaxiallyafter forming.

As has already been mentioned, two-part and multiplepart dies are usedmore particularly in mechanical forges wherein closure of the die jawsexerts a one-sided lateral pressure upon the workpiece. Dies are alsoknown in which the blank assumes a position in the centre of the die andwhere the pressure operates radially from two sides or from all round.

In addition to the above, friction presses are known having divided dieswhich are accommodated in a closed ring, while the divided half-dies areexternally conical in construction. ln this case, the press rams operatein the axial direction of the die. ln order to lilit out the formedworkpiece, the hali-dies are lifted out of the ring together with theworkpiece and after being released by the ring tilt laterally so thatthe workpiece is freed and can be removed, in case the workpieces inquestion have been given projecting portions which would render axialrelease from the die without radial removal of the half-dies animpossibility.

lt is the aim ot the invention to develop a pressing method for coldforming or hot forming workpieces having a varying cross section overtheir length in the direction of operation ot the press rams, from cutlengths of bar o1' prepressed blanks. The method is intended to beapplied more particularly in the use of automatic cross transportpresses and to serve for forming tting bushes, chaplets or the like. Themethod is also intended to be capable of application where crosstransport presses with a plurality of work stations are available,wherein the lank first undergoes preforming or the pressed piece isthereafter subjected to a further machining operation. it is moreover anaim of the invention to develop a device for performing the pressingmethod, which is intended to be capable oi use for example in a knownautomatic cross transport press.

In order to achieve its aim, the invention provides that the blank ispushed axially into a solidly closed die of corresponding cross sectionto the blank, is then pressed between the back ram and the press raminto a second die located immediately axially in front of or behind therst die and composed of at least two radially movable die jaws-the diejaws being closed-and the termed workpiece is then moved out of the diesafter radial opening oi' the die jaws.

When the method according to the invention is applied, and such knownsteps of the method are included as are provided, for example, in thecase of cross transport presses, the following principle of operation isobtained:

First of all a piece of specific length is sheared olf laterally from abar-which may have been heated, for example by means of amedium-frequency heating apparams-and is then pressed into a cake orprovided with a thickened end by pressing, in case the subsequentiinished form so requires, whereupon the blank exists which is intendedto be further formed by application of the method according to theinvention. The said blank is then fed by cross transport to the secondpress device which is constructed appropriately for performing themethod.

The device for performing the pressing method according to the inventionincludes a die support which is movable relative to the back ram,embraces a solidly closed die and accommodates a die consisting of atleast two radially movable guide jaws and located directly axially infront of or behind the solidly closed die, in which the blank can bepressed into the shape of the workpiece by means of the press ram andback ram which operate axially against one another.

The device may further include a stationary back ram with respect towhich the die support, embracing the solidly closed die andaccommodating the die composed of die jaws, is axially displaceable inthe direction of operation of the press ram.

According to a further feature or" the invention, the die carrier may bedisplaceable by the press ram counter to spring power in the directionof operation of the press ram, so that only the press ram need be drivenand the die carrier is also moved in the direction of operation by thesame, whereas it returns to the original position by the spring power.

In further elaboration of the device according to the invention, the diecarrier may be guided in an axially displaceable manner in a carriersleeve which is in turn axially displaceable in the anvil body of thedevice, while the displacement of the carrier sleeve and that of the diemay be eileoted by the press ram. It is obviously also possible toperform the movements of the individual parts by particular drive, whiletheir movements must be appropriately synchronised with one another.

ln a preferred embodiment according to the invention it is provided thatthe axial displacement of the die support and support sleeve in thedirection of operation of the press ram is controlled in such a mannerthat the press ram first displaces the die support alone until the die,composed of die jaws, has been closed and that the die support, supportsleeve and press ram are thereafter displaced in common towards thestationary back ram with forming of the blank in the closed die.

Further according to the invention, the displacement of the die supportmay be effected by the press ram counter to spring power which is lessthan the spring power counter to which the common displacement of `thedie support and the support sleeve can be performed, so that in theiirst place the die support is displaced alone when the press ramattacks it during its movement in the direction of operation. In thiscase it may further be provided that the die jaws automatically closeradially during the movement of the die support in the direction ofoperation of the press ram and automatically open radially in the caseof the movement in the opposite direction. The result of this is thatthe blank may tirst or" all without obstruction assume its initialposition from which pressing of the same is effected in the die whichcloses by radial movement of its jaws after the blank has been insertedinto the solidly closed die.

According to the invention it may be provided for the purpose of closingand opening the die which is composed of individual jaws, that the diejaws are articulated to the die support sleeve with interposition ofelbow levers and are radially guided in the die support in such a mannerthat the die jaws automatically close during movement of the support inone direction, are locked during the pressing operation andautomatically open during movement in the other direction. According tothe invention, provision may be made in a different manner for the diejaws to be supported in the die support against sliding faces or camsor" the die support sleeves which are inclined with respect to the dieaxis in the direction of operation of the press ram, in such a mannerthat the die jaws close during movement of the die support in onedirection, are locked during the pressing operation and automaticallyopen during movement in the other direction.

The radial closure of the die jaws may be eected counter to springpower, so that opening occurs automatically by the spring power.

If the device in question is required for manufacturing at leastpartially hollow workpieces, the press ram may be constructed in knownmanner as a punch with stripper which, after forming of the workpieceand radial opening of the die jaws, withdraws the workpiece while thestripper strips the workpiece from the punch.

Releasing of the finished workpiece from the solidly closed die or fromthe back ram or press ram may also be brought about by other measures,for example in that one of the parts which move relative to one anotherwhen the device opens engages on a shoulder of the linished piece and byits movement separates the latter from the other parts. The press rammay, moreover, enclose a further solidly closed die, as is vdescribed indetail hereinafter.

A device for manufacturing workpieces of varying workpiece crosssections may further be constructed so that the closing and opening ofthe die jaws is chronologically adjustable in accordance with the shapeof the workpiece. In this case it may be provided that the closing andopening of the die jaws is chronologically differential-ie., one jawmoves earlier than the other one.

Further measures for performing the method are described in detailhereinafter with reference to devices according to the invention andwhich are given by way of example only. The igures show:

FlG-S. 1-5 a device for hot forming tting bushes inthe various positionsof the method,

FIGS. 6-8 a device of similar construction for cold forming waistedbodies in the various positions of the method,

FIGS. 9-11 the forming of a chaplet, and

FiGS. 12-15 the processing of a cut length of bar into an axle bodywhich receives its iinished shape by the method according to theinvention in a device for performing the same.v

The devices described hereinafter in detail are intended for use inautomatic cross transport presses in which, for example, three pressingtools are present, wherein the first presses a cut length of bar orlength of wire into a cake which is then further formed in the secondpressing tool by application of the method according to the invention,namely either into the finished piece or into an intermediate piecewhich is converted into the final shape in a third tool.

FIGURES le4 show at 1 a diagrammatically illustrated ilXed part of themachine which carries the tool head from the die side. The same consistsof an anvil body 2 which is secured to the part il. A back ram 3 extendsaxially, is arrested in a specific position after an axial displacementto the left and then forms a stationary back ram. It is retained andguided in a bushing 4 which is fastened in the anvil body Z. The anvilbody 2 extends by its cylindrical body 5 in the axial direction in whicha die support sleeve 6 is located. The latter is axially displaceablethrough the dimension a (FIG. 1) in the cylindrical body 5 of the anvilbody 2, namely to the lett counter to the power of springs '7 which arearranged outside the cylindrical body 5 of the anvil body 2, or in axialrecesses of the same. T he springs 7 are supported by one of their endsagainst supporting faces 2 ot the anvil body 2 and by their other endsagainst the supporting faces 6 or the die support sleeve 6.

A support S is mounted axially displaceably inside the die supportsleeve d and can be displaced to the lett through the distance b (FlG.l), namely counter to the force of springs E5 which are supported by oneof their ends on a supporting face i@ of the die support S and by theirother ends against a supporting face il?, of an inwardly directed iiangeIll of the die support it at the inner end thereof. Secured in theright-hand halt" of the die support 8 is a solidly closed die i3. lnfront of the solidly close die 313 there are .located in the die supportat least two radially movable die jaws ifi with jaw inserts i5. The jawinserts l5 exhibit internally the prole corresponding to the finishedworkpiece. The die jaws lill are articulated by means of levers i6 tothe front end or the die support sleeve 6.

FiGURES l-5 show, on the press ram side, a press ram 17 which is axiallydisplaceable, for example by means of a crankshaft. The press ram 17embraces a stripper 1S which is displaceable to the left counter tospring power and in turn slides in a sleeve 19.

FIG. 1 shows the device at the instant when a length or" bar preformedinto a cake 2li in a preceding pressing tool has been brought betweenthe end faces of the back ram 3 and of the press ram i7 andretainedbetween the same. From this position, the cake 2@ is transferredaxially by displacement of the press ram ll' into the position accordingto FIG. 2. At the same time, the back ram 3 is displaced to the leftinto the xed position. Simultaneously, the displacement of the press ram17 t0- gether with the stripper 18 and the press ram sleeve 19 isassociated with establishment of contact by the stripper 13 and thepress ram sleeve 19 against the en.. face of the die support producingdisplacement of the latter and of the cake 2li to the left. Thedisplacement of the die support 8 occurs within the die support sleevethrough a fraction of the distance b counter to the power of the springs9, until due to the displacement the levers 16 tilt to the left, withwhich movement is associated a radial displacement of the die jaws 14and ot their jaw inserts l5 as far as the closed position which isillustrated in FIG. 2. The further displacement to the left of the pressram i7 with the stripper t@ and the press ram sleeve i9 now acts notsolely upon the die support 8, but on the contrary, the latter, togetherwith the die support sleeve 6, is displaced further to the lett throughthe distance a counter to the power ot the springs '7, until the diesupport sleeve 6 rests against the anvil body 2. This displacementincreases the power of the spring 9 andsimultaneouslythe stronger springpower of the springs 7, which latter exert an iucreasing closing eiiortupon the jaw inserts 15. Since the back ram 3 is stationary during thisdisplacement, the said movement results in the cake Ztl being pressedinto the finished shape 2li', which is clearly shown in detail in FiG.3. The front tip i7 of the press ram i7 penetrates into the cake Ztl andcauses the material to liow axially and radially in such a manner thatit iills the entire remaining cavity between the back ram 3, the pressram 17 and the jaw inserts 15.

Alter the forming operation, the press ram sleeve I19 with the stripperi3 and press ram 17 is withdrawn as shown in lFlG. 4. This is associatedwith the restoration of the die support sleeve d into the originalposition by the power of the springs 7. This movement is shared by thedie support d. When displacement to the right through the distance a iscomplete, further displacement of the die support ii to the rightthrough the distance b follows by virtue of the power of the springs 9.During the displacement to the right of the die support S alone, thelevers lr6 are pivoted once more into their original position. T hispivoting of the levers le outwards causes the die jaws lf2 with the jawinserts l5 to open radially so that the nished piece 2d can be freelywithdrawn mounted on the tip lt of the press ram 17. After thesedisplacements, a displacement of the back ram 3 to the right into theoriginal position has also been eiiected.

FIG. 5 shows how the workpiece 2d is pushed off the tip i7 of the pressram i7 and released by the advance of the stripper l?, to the left fromthe position according to fFlG. 4.

FEGURES 6-8 show, as a further exemplary embodiment, a device formanufacturing similar pressings.

A slightly different structure of the device has been chosen in order toillustrate simultaneously that the device may be elaborated in manydiilerent manners without changing its operating conditions.

lFlGURES 5-8 show at El an anvil body to which a back ram 243- issecured in an axially immovable manner by means of a screwthread ZZ andnut Z3. The anvil body 2l is located within a 'lined part 2.5 oi a crosstransport press which is indicated by a thicl: boundary line. Locatedlikewise in the interior of the parts 25 of the machine is a die supportsleeve 26 which is displaceable through the dimension a. lt iissupported by a face 26 against a piston Z7, the displacement of which tothe left is eitected either counter to spring power or counter topneumatic or hydraulic eliorts. Also mounted in an axially displaceablemanner in the interior of the die support sleeve 26 is a die support Z8.The latter can be dis placed through the distance b to the left withinthe die support sleeve 2d counter to the power of springs 29, Thesprings 39 are supported by one or" their ends against a supporting faceItis" or the die support 2153 and by their other ends against thesupporting face 2l of the anvil body 21. The front end of the back rain24 is tapered and is partially or wholly surrounded by a solidly closeddie Btl which is secured in the die support 23. Located in front of thesolidly closed die 3d are at least two radially displaceable die jaws 3lwhich are retained and guided in the die body 2S by means of guidebushes 32 and 33. Against each of the bushes 32 there is supported aspring 3d which makes Contact by its other end with a shoulder 35 or"the die jaws. The eliect of the springs 3d is that in order for the diejaws 3l to move inwards the power of the springs dit must be overcome,so that the die jaws 3l move automatically radially outwards when thespring power alone operates freely. Outer faces 36 of the die jaws 3lare inclined, namely in such a manner that they malte snug contact withan inclined inner lace 37 of the die support sleeve 2.6. The end face ofthe die support 28 is adapted in shape to the press ram which isdesignated generally FlGURE 6 shows the device in the open positionafter the insertion of a blank 39, namely of a length of bar. Accordingto iFlG. 7, the press ram moves to the left and in doing so makescontact against a portion of the end face or" the die support 2d anddisplaces the die support 2d to the left. T he springs 29 are thereuponcompressed and displacement to the left through the distance b occurs.During this displacement of the die support 25 in the die support sleeve25, the die jaws Til-by their oblique faces 2-6-move along the inclinedface 37 on the die support sleeve 26. This sliding movement produces amovement of the die jaws 31 radially inwards as far as the closedposition (FIG. 7). The closed die jaws 31 and tip 4t) of the press ram3h now form the pressing mould, in front of which is positioned theblank 39 whichby the displacement of the die support Zd to the left-hascome to rest against the end face of the stationary back ram 24. Thefurther displacement of the ram 3d to the left causes furtherdisplacement of the die support sleeve 26 together with the die support23 to the left through the distance a, namely counter to the power ofthe pistons 27 which counteiiacts the displacement. rlisis lastdisplacement is claried by FlG. 8.

Now when the press ram 3S moves haelt to the right linto the originalposition, the die support sleeve 2d, togetl er with the die support Z,first moves to the right through the distance cz by the force or thepistons 27. When this travel is complete, the springs 29 operate anddisplace the die support 2S alone to the right through the distance b,whereupon the die jaws 3l open radially by the force of the springs 34and assume the position illustrated in iFlG. 6. Upon furtherdisplacement of the press ram 3S to the right, the linished pressing canbe run out axially 'from the open die jaws 3d on the spigot oli thepress ram 33 and stripped off.

lFlG. 9 shows a length of bar as an initial blank for manufacturing achaplet. Worlrpiece All is iirst shortened and provided with a headpiece42 in a iirst pressing tool and is then inserted into the deviceaccording to FlG. ll in the open position. .The device according to PEG.1l corresponds in construction to that accor-ding to FIGS. 6 8, so thatreiterated description of the detads may be dispensed with. However,attention should be paid to the conformation of press ram d3 which isprovided with a hole in which there is axially displaeeable a press rodwhereby the position of end face i5 can be locked. Another featureworthy of note is the profiling of end face lo of stripper 47, whereby asecond solidly closed die is achieved, forming a part of the press ramThe blank having the headpiece d2 is therefore formed Within a solidlyclosed die 3u corresponding to the IFEGURES 6 8 and radiallydisplaceable die jaws 3l and a further solidly closed die to form theehaplet 4l' as illustrated in FIG. ll, which shows a device formanufacturing chaplets in the position of the press according to FIG. 8.

FIG. 12 again shows a length of bar which is designated d8. The lengthof bar 4.13 is shaped in a first pressing tool into blank Lili which isprovided with a head Si). The said blank i9 is formed in a devicesimilar to that according to lFlG. ll--i.e., in a device wherein thepress ram forms a second solidly closed die into the tinished pieceaccording to FIGURE-S 14 and 15, which apart from the tapered shank end5l exhibits a atted portion S2 and a longitudinal groove 53, while thelatter portions -52 and 53 are generated by means of the radiallydisplaceable die jaws. rShe die jaws correspond-except for their innerprofiling-to the die jaws which are desig nated 3l in lFiGS. 6 8 and ll.

As Valready mentioned, the device according to the in` vention may beapplied to both hot forming and cold forming workpieces. The primaryidea underlying the construction oi the devices described, which arecapable of considerable structural variations, is their use in crosstransport presses in which a plurality of forming stages are combined.lSince the forming of the workpieces is carried out with the aid ofaxial movements of the press rarn and of the dies, axial drive movementsare present such as are also provided in the case of the preceding orsucceeding tools for preforming and ai'terforming in the case of crosstransport presses. The result of this is that the device according tothe invention admits of fully automatic operation, while obviously thetransport tools customary in the case of cross transport presses areapplied in order to feed the blank to the device and to move it on afterforming to the next process.

What I claim is:

l. A device for forming work pieces comprising; a

back ram, a die support movably supported with respect to said back ram,a solidly closed iirst die in said die support, a second die in said diesupport adjacent said first die, said second die comprising radiallymovable die jaws, and a press ram aligned with said back ram and movabletoward and away from said back ram for cooperation therewith to formwork pieces in said dies.

2. yA device for forming work pieces comprising; a back ram, a diesupport movably supported with respect to said back ram, a solidlyclosed iirst die in said die support, a second die in said die supportadjacent said rst die, said second die comprising radially movable diejaws, and a press ram aligned with said back ram and movable toward andaway from said back ram for cooperation therewith to form work pieces insaid dies, said die support surrounding said back ram and beingresiliently biased toward said press ram, said dies being supported insaid die support co-axially with said rams.

3. A device for forming work pieces comprising; a back ram, a supportsleeve co-axial with said back ram and resiliently urged in onedirection axially of said back ram, a die support reciprocably in saidsleeve and resiliently biased therein in the said one direction, aclosed rst die in said die support, a second die in said die supportadjacent said rst die and comprising radially movable die jaws, a pressram aligned with said back ram and spaced therefrom in the said onedirection, said press ram being movable toward said back ram, and meansoperated by said press ram for moving said die support and said supportsleeve in a direction opposite to said one direction.

4. A device for forming work pieces comprising; a back ram, a supportsleeve co-axial with said back ram and resiliently urged in onedirection axiaiiy of said back ram, a die support reciprocably in saidsleeve and resiliently biased therein in the said one direction, aclosed iirst die in said die support, a second die in said die supportadjacent said rst die and comprising radially movable die jaws, a pressram aligned with said back ram and spaced therefrom in the said onedirection, said press ram being movable toward said back ram, and meansoperated by said press ram for moving said die support and said supportsleeve in a direction opposite to said one direction, the said movementof said die support in the direction opposite to said one directionbeing operable for moving said die jaws toward each other while movementthereof in the said one direction will bring about movement of said diejaws away from each other.

5. A device for forming work pieces comprising; a back ram, a supportsleeve co-axial with said back ram and resiliently urged in onedirection axially of said back ram, a die support reciprocably in saidsleeve and resiliently biased therein in the said one direction, aclosed rst die in said die support, a second die in said die supportadjacent said rst die and comprising radially movable die jaws, a pressram aligned with said back ram and spaced therefrom in the said onedirection, said press ram being movable toward said back ram, and meansoperated by said press ram for moving said die support and said supportsleeve in a direction opposite to said one direction, the said movementof said die support in the direction opposite to said one directionbeing operable for moving said die jaws toward each other while movementthereof in the said one direction will bring about movement of said diejaws away from each other, the

resilient bias exerted on said sleeve being greater than the resilientbias being exerted on said die support whereby the die support rst movesrelative to the support sleeve and thereafter the die support and sleevemove in unison.

6. A device for forming work pieces comprising; an anvil bod a back ram,a die support sleeve reciprocable in said anvil body and co-axial withsaid back ram, yieldable means interposed between said anvil body andsaid support sleeve to resist movement of the sleeve toward the body, adie support reciprocably mounted in said sleeve and yieldable meansbetween the die support and the sleeve urging the support in said onedirection in the sleeve, a iirst closed die in said die support, asecond die in said die support adjacent said first die and comprisesradially movable jaws, press ram co-axial with said back ram and spacedtherefrom in said one direction, a sleeve surrounding said press ram,said press ram being movable toward said back rain for carrying a workpiece therebetween into said die, said sleeve being engageable with saiddie support for moving the die support toward said support sleeve andthen movin;7 said die support and support sleeve together toward saidbody, and means connecting saidfjaws with said support sleeve operablein response to movement of the die support toward the support sleeve forclosing said jaws, said press ram comprising a punch portion on the endthereof arranged to penetrate the work piece being formed and towithdraw the work piece from the dies upon retraction of the press ram,and stripper means associated with the press ram operable for strippinga complete work piece from said punch portion.

7. A device for forming work pieces according to clairn 6 in which themeans connecting the die jaws to said support sleeve comprise linkspivoted at their one ends to the support sleeve and at their other endsto said die jaws.

8. A device for forming work pieces according to claim 6 in which thelast mentioned means comprise inclined surfaces on the support sleeveand end portions on the die jaws engage said inclined surfaces.

9. A device for forming work pieces according to claim 8 in which springmeans are provided urging said die jaws outwardly.

10. A device for forming work pieces according to claim 6 in which themeans for moving said die jaws radially is operable for moving theindividual jaws sequentially.

11. A device for forming work pieces according to claim 6 in which saidback ram is xedly supported relative to said anvil body.

12. A device for forming work pieces according to claim 6 in which saidback ram is reciprocably mounted relative to said anvil body.

References Cited in the tile of this patent UNITED STATES PATENTS438,498 Smith Oct. 14, 1890 1,027,383 Glover May 21, 1912 1,977,164Wilcox Oct. 16, 1934 2,978,932 Frueaufi Apr. 11, 1961 FOREIGN PATENTS381,718 Germany Sept. 24, 1923

1. A DEVICE FOR FORMING WORK PIECES COMPRISING; A BACK RAM, A DIESUPPORT MOVABLY SUPPORTED WITH RESPECT TO SAID BACK RAM, A SOLIDLYCLOSED FIRST DIE IN SAID DIE SUPPORT, A SECOND DIE IN SAID DIE SUPPORTADJACENT SAID FIRST DIE, SAID SECOND DIE COMPRISING RADIALLY MOVABLE DIEJAWS, AND A PRESS RAM ALIGNED WITH SAID BACK RAM AND MOVABLE TOWARD ANDAWAY FROM SAID BACK RAM FOR COOPERATION THEREWITH TO FORM WORK PIECES INSAID DIES.